Ammunition priming composition



Patented Aug. 22, 1944 UNITED STATES PATENT GFFHCE AMMUNITION PRIIVIING COIVIPO SITION Philip H. Burdett, Bridgeport, and Gordon M.

Calhoun, Fairfield, Conn., assignors to Remington Arms Company, Inc., a corporation of Delaware No Drawing. Application May 24, 1941, Serial No. 394,994

4 Claims.

This invention relates to priming mixtures for ammunition and comprises the discovery that several salts of triazoacetic acid possess properties which render them particularly valuable as ingredients of such mixtures.

Conventional priming mixtures comprise three classes of ingredients:

First, a fuel or substance tobe burned with the production of a flame of sufiicient heat and into of the priming-mixture. The normal lead triazoacetate, which probably has the formula:

may be prepared by the double decomposition tensity to effectively ignite propellant pow- The percussion-sensitive ingredient is frequently referred to as an explosive, because it is capable of being disrupted by a blow. There are, however, certain explosives, of which lead styphriate is typical, which are not of themselves dependably susceptible to explosion by a firing pin blow, but after ignition perform the function of a combustion initiator in an eminently satisfactory manner. With such an explosive it is desirable to use another ingredient ordinarily referred to as a sensitizer. Such sensitizers may not of themselves be more sensitive to percussion than the explosive they sensitize, but in admixture with an explosive, such as lead styphnate, form a composition which is not only quite highly sensitive to percussion but under percussion explodes without undue violence and with the creation of the heat and pressure ample to produce the oxidizer-fuel reaction.

It has been found that several salts of triazoacetic acid, particularly the lead salt, are very valuable sensitizers for ammunition priming mixtures of the lead styphnate type. A typical mixture consists of:

Per cent Lead styphnate 32 Lead nitrate 30 Lead sulfocyanate 8 Lead triazoacetate 10 Glass Other triazoacetates, such as those of silver or potassium, may replace the lead salt with desirable results.

Other combustion initiators, oxidizers (particularly the non-corrosive type) and fuels may be used and the proportions of the ingredients varied widely. A practical range of proportions of the salt of triazoacetic acid is from about 1% method from the potassium salt of triazoacetic acid and lead nitrate. It forms large white glistening needles somewhat soluble in cold water.

The normal silver salt may be prepared in a It forms pure white crystals,

similar manner.

In the preparation of the potassium salt, ethyl chloroacetate is refluxed with sodium azide in alcohol diluted with enough water to keep the sodium azide in solution. After several hours a comparatively large volume of water is added, and the oily layer separated by means of a separatory funnel. This non-aqueous layer is treated directly (or' after distillation) with aqueous potassium hydroxide. The potassium salt precipitates as creamy white plates, upon evaporation of the resulting solution.

The uranyl salt, probably having the formula:

is obtained as a bright yellow powder upon evaporation and cooling of the solution obtained by adding 1 part of triazoacetic acid (NaCHzCOOH) in 8 parts of water to 2.51 parts of uranyl nitrate Per cent Normal lead triazoacetateu; 10 Lead styphnate s 32 Lead sulfocyanate 8 Lead nitrate 30 Glass 20 2. An ignition mixture containing approximately:

I Per cent Salt of'triazoacetic acid 10 Lead styphnate 32' Lead sulfocyanate 8 Lead nitrate- 30 Glass 20 the salt of triazoacetic acid being that of a metal from the group consisting of potassium, silver and 4. A priming mixture for ammunition containlead. I ing lead styphnate and a salt of triazoacetic acid,

3. An ammunition priming mixture comprising said salt being that of a metal from the group an oxidizer, a. fuel, a combustion initiator, and 9. consisting of potassium, silver, lead and uranyl.

salt of triazoacetic acid as a sensitizer, said salt 5 being that of a metal from the group consisting PHILIP H. BURDETT.

of potassium, silver, lead and uranyl. GORDON M. CALHOUN. 

